基于遥感数据的内蒙古化德地区矿化蚀变信息提取及找矿指示

Extraction of Mineralization Alteration Information and Prospecting Indications Based on Remote Sensing Data in the Huade Area, Inner Mongolia

摘要: 内蒙古乌兰察布市化德县地处华北地台北缘白云鄂博裂谷带东段，是华北陆块北缘重要的金、银、铜、铅、锌、钨、钼等多金属成矿区，近年来相继发现了幸福村金矿、二道沟铜金矿、三胜村钨钼矿床、长春沟–达盖滩铅锌矿、达盖滩钼多金属矿等一批矿床(点)，具有较大的找矿潜力。为充分发挥遥感技术在矿产资源勘查中的先导性作用，本文基于ASTER和Landsat-8 OLI两种遥感数据，依据研究区典型蚀变矿物的光谱特征，采用主成分分析方法分别提取了铁染蚀变信息和羟基蚀变信息。通过蚀变异常信息的空间分布规律分析，结合区域地质图及构造研究成果进行叠加分析，成功圈定了数条蚀变异常带。研究结果表明，化德县遥感蚀变异常的展布方向与区域北西向和近东西向断裂构造带走向基本一致，成矿热液活动明显受断裂构造控制。本文研究可为华北地台北缘寻找同类型多金属矿床提供遥感技术参考，对化德县及其外围找矿工作具有一定的指导意义。

Abstract: The Huade County of Ulanqab City, Inner Mongolia, is located in the eastern segment of the Bayan Obo rift zone on the northern margin of the North China Platform. It is an important polymetallic metallogenic region for Au, Ag, Cu, Pb, Zn, W, and Mo along the northern margin of the North China Craton. In recent years, a number of deposits (occurrences) have been discovered successively in this area, including the Xingfucun gold deposit, Erdaogou copper‑gold deposit, Sanshengcun tungsten‑molybdenum deposit, Changchungou‑Dagaitan lead‑zinc deposit, and Dagaitan molybdenum‑polymetallic deposit, indicating considerable prospecting potential. To fully leverage the pioneering role of remote sensing technology in mineral exploration, this study utilized both ASTER and Landsat‑8 OLI remote sensing data. Based on the spectral characteristics of typical alteration minerals in the study area, the principal component analysis (PCA) method was employed to extract iron‑stained alteration information and hydroxyl alteration information, respectively. Through analysis of the spatial distribution patterns of the alteration anomalies, combined with overlay analysis using regional geological maps and structural research results, several alteration anomaly zones were successfully delineated. The results show that the distribution direction of the remote‑sensing alteration anomalies in Huade County is generally consistent with the strike of the regional NW‑trending and near‑E‑W‑trending fault structural belts, indicating that the hydrothermal mineralization activities are obviously controlled by fault structures. This study can provide a remote‑sensing technical reference for the exploration of similar polymetallic deposits on the northern margin of the North China Craton, and has certain guiding significance for prospecting work in Huade County and its surrounding areas.